@Scale 2019: Disaggregated Graph Database with Rich Read Semantics
Access to the social graph is a mission critical workload for Facebook. Supporting a graph data model is inherently difficult because the underlying system has to be capable of efficiently supporting the combinatoric explosion of possible access patterns that can arise from even a single traversal. In this session, we will discuss the introduction of an ecosystem of disaggregated secondary indexing micro-services which are kept up to date and consistent with the source of truth via access to a shared log of updates into our serving stack. This work has enabled Facebook to efficiently accommodate access pattern diversity by transparently optimizing graph accesses under the hood. It is responsible for an over 50% reduction in read queries to the source of truth and has unlocked the ability for product developers to access the graph in new game changing ways. We will also discuss the logical next steps that we are exploring as a consequence of this work.